Chains fitted with cutting or abrading attachments are typically employed in a variety of applications. For example, trenching machines (commonly referred to as "trenchers") incorporate various types of cutting attachments onto chains. The chains are typically sprocket driven and are revolved about an extended arm or boom. With the chain revolving about the boom, the boom is lowered into contact with the ground whereby the cutting attachments remove soil, rock and other spoil from the ground. A trench is formed in the ground where the chain and its cutting attachments have removed soil and other materials.
Trenching chains are subjected to tremendous abrasive forces during operation. The outer surface of the chain's sidebars and the pin heads used to interconnect the links of the chain are particularly susceptible to abrasion and wear which primarily results as the outer sidebar surface and pin head scrape against the walls of the forming trench. Wear also tends to occur to the lower edge of the sidebars as the chain travels along the boom. When cutting through particularly difficult materials such as rock, a new chain may be operated for only a few hours before a wear-related failure of the chain occurs. As can be appreciated, such wear-related failures reduce productivity and increase the cost of operating conventional trenchers.